Pipe or plumbing systems often include access openings or ports that allow the interior of the pipes of the pipe system to be inspected, cleaned, and/or tested. Access opening configurations for such pipe systems can vary in size and shape, although many configurations are standardized. In one common configuration, one or more access openings (often referred to as a “clean-outs”) are provided of cylindrical pipe that extends away from the axis of the main pipe section. Clean-outs may extend from a main pipe section at any angle. Those that extend approximately 90 degrees from the main pipe section are commonly called “clean-out tees” (referring to the T-shape created by the intersecting pipe sections).
Clean-outs are also used to access areas of the pipe system in order to test the integrity of the pipe system. Currently, this is accomplished by placing temporary test plugs in the clean-outs or other portions of the pipe system accessible through the clean-outs. A test media, such as a liquid or gaseous material (typically water or air) is then introduced into the pipe system for a period of time to determine if there are any leaks. After successful testing, the test plugs are removed. Existing test plugs can be categorized into mechanical plugs and pneumatic plugs. Mechanical test plugs include devices that seal pipe systems via mechanical activation, such as by turning a threaded connection member to expand an elastomeric ring that seals against an inner surface of a pipe section. Pneumatic plugs include elongate elastomeric bladders that are attached directly to an air source. The bladders are inserted into the pipe system through the clean-outs or other access points and are then inflated to seal the pipe section. After testing, the test plugs are deflated or deactivated and then removed from the pipe system.
In some instances, existing pneumatic and mechanical plugs can present unpleasant conditions for a user. For example, to test a vertical pipe system having a clean-out tee, a common procedure includes inserting a pneumatic test plug through the access opening and into the pipe section above the clean-out, where it is inflated to seal a portion of the pipe section. Another common procedure includes inflating a pneumatic test plug in the access port of the clean-out tee so that it spans across the clean-out to seal a portion of the pipe section. Regardless of which type of test plug is used, the plugs are often subjected to extremely high pressures from the test media. It is not uncommon for a test plug to have several stories of water directly above the plug in the pipe section. Properly sealing and safely releasing such a large head pressure is a problem for many of these test plugs. For example, releasing the pressure using a test plug of the first type may force the test plug downward and spray the test media out through the access port. Test plugs of the second type may have great difficulty sealing many types of clean-out fittings because of varying types of surfaces on the inner surface of pipes and because of the limited sealing areas. Additionally, test plugs of both types may lose air pressure prior to or during a test.
As a result, there is a need for an improved test plug for use in sealing a pipe-section having a clean-out where the clean-out extends at an angle from the pipe section. The improved test plug should be capable of mechanically sealing the pipe section and blocking test media from other portions of the pipe section. It should also be capable of safely releasing test media into other portions of the pipe section. Various embodiments of the test plug should also be capable of sealing pipe sections with clean-outs that extend at various angles from the pipe section. Additionally, the improved test plug should be easy to use.